Open chamber gun ammunition feed system



Feb. 3., 1970 MQJ. BARNARD 3,492,913

OPEN CHAMBER GUN AMMUNITION FEED SYSTEM Filed March 11, 1968 3Sheets-Sheet 1 El 2ML i4/cuasi. J2 .Bmeunnp Feb, 3, 1970 M. J. BARNARD3,492,913

OPEN CHAMBER GUN AMMUNITI'ON FEED SYSTEM Filed March 1l, 1968 3Sheets-Sheet 2 34N. *L 55s-'5 im() l Feb. 3., 1970 J. BARNRD 3,492,913

OPEN CHAMBER GUN AMMUNITION FEED SYSTEM Filed March 11, 1968 5Sheets-Sheet 3 United States Patent O 3,492,913 OPEN 'CHAMBER GUNAMMUNITION FEED SYSTEM Michael J. Barnard, Torrance, Calif., assignor toI'RW Inc., Redondo Beach, Calif., a corporation of h10 Filed Mar. 11,1968, Ser. No. 712,214 Int. Cl. F41d 9/06 U.S. 'Cl. 89-33 11 ClaimsABSTRACT 0F THE DISCLOSURE An open chamber gun system having `ammunitioninfeed means, an open chamber gun with a rotary ammunition cylinder, anda transfer means for receiving open chamber ammunition rounds laterallyin succession from the infeed means and transferring the roundslaterally in succession into the cylinder firing chambers. The roundsare releasably secured to a belt which is fed endwise through a transferstation where the rounds are stripped from the belt as they enter thefiring chambers.

BACKGROUND OF THE INVENTION Field of the invention The invention relatesgenerally to guns and more particularly to a novel open chamber gunsystem.

Prior Art Open chamber guns are known in the art. Such guns, forexample, are disclosed in prior art Patent Numbers 2,865,126; 2,847,784;2,983,223; 2,831,401; 3,041,939; and 3,046,890. Generally speaking, anopen chamber gun is characterized by a breech frame having a ring strapand containing a rotary breech cylinder. This breech cylinder has anumber of ii'ring chambers circumferentially spaced about and openinglaterally through the cirmumference of the cylinder. During operation ofthe gun, the cylinder is driven in rotation to rotate the firingchambers in succession through ammunition infeed, tiring, and ejectionpositions. The open side of each firing chamber, when in infeedposition, registers with a lateral ammunition infeed opening in thebreech frame to permit lateral infeed movement of an ammunition roundinto the chamber. When in ring position. the open side of each firingchamber is closed by the breech frame firing strap, to condition the gunfor firing of an ammunition round in the chamber. The open side of eachfiring chamber, when in ejection position, lregisters with a lateralejection opening in the breech frame to permit lateral ejection of thespent cartridge case of a fired round, as well as an unred round, fromthe chamber. A characteristic feature of the open chamber guns disclosedin the aforementioned prior art patents resides in the complementary,generally triangular round shapes of the firing chambers and ammunitionrounds. In this regard, it will be observed in the patent -drawings thateach firing chamber and ammunition round has a generally triangularround shape in transverse cross-section, such that an ammunition roundpositioned in a firing chamber has one curved side exposed at the openside of the firing chamber. At least this exposed side of each round hassubstantially the same radius of curvature as the breech cylinder and issubstantially ush with the cylinder circumference. The ring chambers andammunition rounds may have either a generally equilateral triangularround shape, in which case, all three sides of each round and the twosides of each ring chamber have the same radius of curvature as the:breech cylinder, or a4 generally isosceles triangular round shape, inwhich case only the exposed side of each round has the same radius ofcurvature as the breech 3,492,913 Patented Feb. 3, 1970 cylinder. Withthis latter configuration, the two remaining side of each round and thetwo side Walls of each firing chamber have a common radius of curvaturewhich differs from that of the cylinder. An open chamber gun may embodyeither a xed barrel or a rotary barrel construction. A xed barrel openchamber gun is one in which the gun barrel or barrels are secured to andremain stationary with the breech frame. During firing operation of sucha fixed |barrel gun, the breech cylinder is driven in intermittentrotation in such a way that each cylinder tiring chamber is momentarilyarrested in firing position, and a round is fired in the chamber whilethe latter remains stationary in this position. A rotary barrel openchamber gun, on the other hand, has a number of gun barrels which aresecured to the breech cylinder, in coaxial alignment with its firingchambers, respectively, and rotate with the cylinder. During ringoperation of such a rotary barrel gun, the breech cylinder and barrelsare driven in continuous rotation, and an ammunition round is fired ineach chamber during rotation of the latter through its ring position.The earlier mentioned Patent Number 3,041,939 discloses a rotary barrelopen chamber gun. The remaining patents disclose xed barrel open chamberguns. As is well known to those versed in the art, a major advantage ofa rotary barrel gun over a fixed barrel gun resides in the higher ringrate `of the rotary barrel gun. It will become evident as thedescription proceeds that the present invention may be utilized toadvantage in connection with both fixed barrel and rotary barrel openchamber guns. However, the invention is particularly concerned with andwill be disclosed in connection with its application to a rotary barrelopen chamber gun.

Briefly, during firing operation of an open chamber gun, the openchamber ammunition rounds are fed laterally to the breech cylinder insuch a way that each round undergoes lateral infeed movement into acylinder firing chamber in infeed position, through the open side of thechamber. The round then rotates laterally with its containing chamber tofiring position, where the round is red. After ring, the spent cartridgecase of the round is rotated laterally to ejection position and ejectedlaterally from the firing chamber through the open side of the chamber.

The aforementioned prior art patents disclose various ammunition feedmechanisms for feeding open chamber ammunition rounds to the openchamber gun cylinders. These existing ammunition feed mechanisms, whilecapable of employment in relatively low firing rate guns, are ill-suitedto or incapable of employment in high filing rate guns. In thisconnection it should be noted that a high firing rate open chamber gun,in the present context, is one which involves an ammunition infeed rateon the order of 36,000 rounds per minute into the firing chambers of arotating breech cylinder whose rim velocity is on the order of 33 feetper minute. The stringent requirements imposed by these operatingparameters on an ammunition feed mechanism are obvious and, as alreadynoted, are incapable of satisfaction by the existing ammunition feedmechanisms.

SUMMARY OF THE INVENTION The present invention provides a novel openchamber gun system of the class described. A particularly unique andimportant advantage of this system resides in its high firing ratecapability. In this regard, it will become evident as the descriptionproceeds that the invention is particularly adapted for embodiment in ahigh firing rate, rotary barrel open chamber gun of the kind discussedabove. It will be recognized by those versed in the art as thedescription proceeds, however, that while the present gun systempossesses the inherent and advantageous capability of high firing rate,it is not limited in usefulness to high tiring rate applications.

`In general terms, the present gun system is characterized by an openchamber gun and an ammunition feed mechanism for feeding open chamberrounds in succession to the firing chambers in the gun cylinder.According to one feature of the invention, the feed mechanism embodiesan ammunition infeed means for conveying the rounds in succession alonga prescribed path of motion from an ammunition storage facility, such asan article storage magazine, to an infeed transfer station, and anammunition transfer means for receiving the rounds in succession fromthe infeed means at the infeed transfer station, transporting the roundsin succession to an outfeed transfer station with the rounds disposed inpredetermined spaced and oriented relation to their direction line ofmovement between the Stations, and dispensing the rounds in successionto the gun cylinder at the outfeed station in the proper timed relationto the cylinder rotation and proper attitude to enter the cylinder ringchambers. In the particular embodiment of the invention which has beenselected for illustration in this disclosure the transfer means is arotary transfer wheel having axially extending ammunition receivingpockets which are spaced circumferentially about and open laterallythrough the circumference of the wheel in such a way that each pocket isconditioned to laterally receive an ammunition round through its openside from the infeed means and to position the contained round parallelto the transfer wheel axis. The transfer wheel and breech cylinder aregenerally tangently disposed at the outfeed transfer station and aredriven in unison in such a way that the ammunition rounds aretransferred laterally in succession from the transfer wheel into thecylinder firing chambers, through the open sides of these chambers.

As will appear from the ensuing description, the ammunition feedmechanism of the invention may be employed to handle and feed unattachedor beltless ammunition rounds, which are not joined to one another inany way. A further aspect of the invention, however, is concerned with aunique web or belt-type ammunition feeding and dispensing mechanism forthe present open chamber gun system. According to this inventive aspect,the ammunition rounds are adhesively bonded or otherwise releasablysecured to one side of a conveyor web or belt which is trained about thetransfer wheel in such a way that the rounds engage driving lugs on thewheel. Rotation of the transfer wheel drives the rounds and belt throughthe feed system to the gun. This belt-type feeding and dispensingmechanism serves both as a transport mechanism for transportingammunition rounds laterally in succession from an ammunition magazine tothe breech cylinder of the open chamber gun, and as an ammunitiontransfer mechanism for positively timing and orienting the incomingrounds for proper entrance into the breech firing chambers. The conveyorweb or belt is stripped from each ammunition round as the latter entersits ring chamber, thus to release the round from the web for rotationwith its containing tiring chamber to firing position.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is a side elevation of an open chamber gun system according tothe invention, which, in this instance, consists of a rotary barrel openchamber gun and an ammunition feed system for feeding open chamberammunition rounds to the gun;

FIG. 2 is an enlarged section taken on line 2-2 in FIG. 1;

FIG. 3 is a further enlarged section taken on line 3 3 in FIG. 2;

FIG. 4 is a section taken on line 4-4 in FIG. 3;

FIG. 5 is a section taken on line 5-5 in FIG. 3; and

FIG. 6 is a section taken on line 6-6 in F-IG. 2.

4 DESCRIPTION OF THE PREFERRED EMBODIMENT In general terms, theinvention provides an open chamber gun system 10, including an openchamber gun 34 having a rotary open chamber cylinder, and an ammunitionfeeding and dispensing mechanism 14 for transporting or feeding openchamber ammunition rounds 16 in succession from an ammunition storagefacility 17 to the cylinder and dispensing the round in succession tothe cylinder in such a way that the rounds are presented to the cylinderin accurately timed relation to the rotation of the cylinder with eachround oriented in a predetermined attitude relative to the cylinder. Theammunition feeding and dispensing mechanism 14 illustrated, which willbe enceforth referred to simply as a feed mechanism, comprises an infeedmeans 18 and a transfer means 20. The infeed means 18 conveys the rounds16 in succession along a prescribed path of movement to an infeedtransfer station Si. The transfer means 20 includes a driven transfermechanism 22, in this instance a transfer wheel, having ammunitionreceiving means 24 which are movable through the infeed transfer stationin succession. The transfer mechanism receives the rounds 16 insuccession from the infeed means 18 at the infeed transfer station andtransports the rounds to an outfeed transfer station So. Located at theoutfeed transfer station is a transfer guide 26 for effecting outfeedtransfer movement of each round 16 from the transfer mechanism to thegun cylinder 12 as the round travels through the outfeed station. Drivemeans 28 are provided for driving the cylinder 12 and the transfermechanism 22 in synchronism. The ammunition receiving means 24 of thetransfer mechanism are arranged to locate the rounds 16 in accuratelyspaced relation along and in a predetermined attitude relative to theirdirection line of movement from the infeed station S1 to the outfeedstation So. As will appear presently, the motions of the gun cylinder 12and the transfer mechanism 22 are so timed, and the rounds 16 on thetransfer mechanism are so spaced and oriented, that the rounds arepresented or transferred to the cylinder at the outfeed transfer stationS0 in accurately timed relation to the cylinder rotation with the roundsdisposed in a predetermined attitude relative to the direction line ofmovement of the cylinder through the outfeed station. The gun cylinder12 has a number of firing chambers 30 spaced circumferentially about andopening laterally through the circumference of the cylinder. The rounds16 are transferred laterally to the cylinder in such manner that eachundergoes lateral infeed movement into a cylinder chamber 30 through theopen side of the chamber as the latter rotates through the outfeedtransfer station So.

As noted earlier, a further important aspect of the present invention isconcerned with a unique web or belt-type article feeding and dispensingmeans for the ammunition rounds 16. According to this aspect of theinvention, the rounds are releasably secured in spaced relation to aconveyor web 32 which which is trained about the transfer Wheel 22. Aseach round approaches the outfeed transfer station So, it is directedalong a path of movement which diverges from the path of web movementthrough the station in such a way that the round is stripped from theweb. According to the preferred practice of the invention, the roundsare releasably secured to the web by an adhesive bond having asufiiciently high shear strength to effect transfer of the drivingforces from the rounds to the web and a sufficiently low peel strengthto permit stripping the rounds from the web.

Briefly, in operation of the open chamber gun system 10, the guncylinder 12 and transfer wheel 22 are driven in synchronism to drive theconveyor web 32 endwise through the infeed means 18 to the infeedtransfer station Si. At this station, the rounds 16 and conveyor webpass from the infeed means to the transfer wheel and travel with thiswheel from the latter station to the outfeed transfer station S0. Duringtheir transfer movement from the infeed means to the transfer wheel, therounds enter the ammunition receiving means 24 on the transfer wheel andare thereby drivably engaged with the wheel as well as accurately spacedand oriented relative to their path of motion on the wheel. As eachround 16 approaches the outfeed transfer station S0, the round engagesthe transfer guide 26. This transfer guide directs each round along apath of movement which diverges from the path of movement of theconveyor web 32 and merges with the path of movement of the gun cylinderchambers 30 in such a way that each round is stripped from the web andsimultaneously undergoes outfeed transfer movement from the transferwheel into a cylinder chamber.

The particular open chamber gun shown is a high firing rate, rotarybarrel gun of the kind referred to earlier. The illustrated open chambergun has a breech frame 36 in which` the breech cylinder 12 is rotatablymounted by front and rear bearings 38, 40. The cylinder chambers 30constitute firing chambers. As already noted and illustrated in thedrawings, these firing chambers are circumferentially spaced about andopen laterally through the circumference of the cylinder. The front endof the breech cylinder 12 projects forwardly through an opening in andis exposed at the front end of the breech frame 36. Secured to andextending forwardly from the front end of the cylinder are a number ofgun barrels 42. These barrels are equal in number to and are coaxiallyaligned with the iiring chambers 30. Each barrel contains a bore whichopens rearwardly to the corresponding firing chamber. It is evident atthis point, therefore, that the breech cylinder 12 and barrels 42 rotatein unison.

It will be recalled that the present gun system embodies a drive means28. In this instance, the drive means comprise a motor 46 mounted on therear end of the breech frame 36. The shaft of this motor is coupled tothe rear end of the breech cylinder 12 for driving the cylinder inrotation in a counterclockwise direction, as viewed in FIG. 2. Then thebreech cylinder is thus driven, each cylinder firing chamber undergoesrotation through infeed, firing and ejection positions in sequence. Whenin infeed position, the open side of each firing chamber registers withan ammunition infeed opening 48 in the breech frame 36. This infeedopening is located at and faces the outfeed transfer station So of thearticle transfer means 20. When in firing position, the open side ofeach firing chamber is closed by the breech frame firing strap 50 tocondition the gun for firing an ammunition round in the chamber. The gunis equipped with firing means (not shown) for firing a round in eachfiring chamber 30 during rotation of the latter through its firingposition. When in ejection position, the open side of each firingchamber registers with an ejection chute 52 on the breech frame 36.

The illustrated ammunition rounds 16 comprise open chamber ammunitionrounds to be fired in the open chamber gun 34. These ammunition roundsare conventional and, accordingly, need not be described in detail.Suffice it to say that each ammunition round has a generally triangularround shape in transverse cross-section. In this instance, theammunition has a generally equilateral triangular round shape similar tothat disclosed in the majority of the aforementioned prior art patents.Each side of a round has a radius of curvature substantially equal tothe radius of the breech cylinder 12. The cylinder firing chambers 30also have a generally triangular round shape in transverse cross-sectionand are sized to complement the ammunition rounds 16 in such a way thatwhen a round is positioned in a firing chamber, the exposed side of theround is substantially flush with the cylinder circumference.

The ammunition rounds 16 are adhesively bonded to one side of theconveyor web 32, which thus serves as an ammunition belt. This belt maycomprise various materials but is preferably a Mylar tape. As shown bestin FIG. 2, the ammunition rounds 16 are secured to the belt 32 at spacedintervals with the longitudinal axis of each round extending normal tothe length of the belt. The center distance between adjacent ammunitionrounds is approximately equal to the circumferential spacing between theadjacent cylinder firing chambers 30. As may be best observed in FIG. 3,the ammunition rounds 16 have a length somewhat greater than the widthof the belt 32 and are centered endwise relative to the belt, wherebythe ends of each round project a distance beyond the longitudinal edgesof the belt.

We turn now to the ammunition feed mechanism 14. The transfer mechanismor wheel 22 of this ammunition feed mechanism has a generallycylindrical drum 54 closed at one end by an integral end wall 56 and ashaft 58 integrally joined to and extending coaxially from the end wall.This shaft has a bearing shoulder 60 adjacent the end wall and an outersplined end 62. The end of the transfer wheel drum S4 remote from theend wall 56 is open.

Transfer wheel 22 is located directly opposite the ammunition infeedopening 48 in the breech rframe 36 of the open chamber gun 34. The axisof this transfer wheel parallels the axis of the breech cylinder 12. Thecircumference of the transfer wheel is disposed in close proximity tothe circumference of the cylinder and the adjacent curved face of thefiring strap 50. Extending laterally from the breech frame 36, at the-front and rear ends of the transfer wheel 22 are a pair of front andrear transfer wheel mounting brackets 64, 66. The transfer wheel shaft58 extends through the rear mounting bracket 66 and is rotatablysupported in this bracket by a bearing 68, the inner face of which issecured to the shaft bearing shoulder 60. Concentrically positionedwithin the transfer wheel drum 54 is a generally cylindrical camassembly 70 whose function will be explained presently. Suffice it tosay at this point that the cam assembly 70 includes an inner supportingmember 72 having a central bearing shoulder 74 and integral front andrear shafts 76, 78 extending coaxially from opposite sides of theshoulder. The front shaft 76 extends through the front transfer wheelsupporting bracket 64 and is threaded to receive a nut 80 for rigidlysecuring the supporting member 72 to the bracket. The bearing shoulder74 of the supporting member 72 is positioned within the front end of thetransfer wheel drum 54, and the rear shaft 78 of the member extendscentrally through the drum into a blind bore in its rear end wall 56.Mounted on the bearing shoulder and the rear end of the shaft arebearings 82, 84 which rotatably support the transfer wheel on thesupporting member 72. The transfer wheel 22 is thus supported on thebreech frame 36 lfor rotation on an axis parallel to the breech cylinder12.

It will be recalled that the transfer wheel 22 is driven in synchronismwith the breech cylinder 12 by the drive means 28. To this end, thedrive means comprises a drive gear 86 which is coaxially keyed on therear end of the cylinder so as to rotate with the latter when thecylinder is driven -by its motor 46. Rotatably supported on the transferwheel shaft 58, between its bearing shoulder 60 and splined end 62, is adriven gear 88 which meshes with the drive gear 86. The splined end 62of the shaft slidably mounts a drive dog or clutch collar havinginternal splines which mesh with the shaft splines to restrain thecollar and shaft against relative rotation. Clutch collar 90 is movableaxially of the transfer wheel shaft 58 between a left-hand or forwardtransfer wheel drive position and a right-hand or rear transfer wheellock position in FIG. 3. Integrally formed on the confronting ends ofthe driven gear 88 and the clutch collar 90 are clutch drive teeth 92which interengage to drivably couple the gear to the transfer wheel 22when the collar occupies its forward drive position. Rigidly secured tothe rear end of the breech frame 36, rearwardly of the clutch collar 90,is a mounting plate 94 to which the breech cylinder drive motor 46 isattached. On the front surface of this plate and the rear face of theclutch collar 90 are clutch lock teeth 96 which interengage to lock thetransfer wheel against rotation when the clutch collar occupies its rearlock position. It is evident at this point that the breech cylinder 12is driven continuously in rotation whenever its drive motor 46 isenergized. The transfer wheel 22, on the other hand, is adapted to beselectively coupled to the drive motor for rotation in synchronism withthe breech cylinder and locked against rotation while the breechcylinder continues to turn by shifting of the clutch collar 90 betweenits drive and lock positions.

Clutch collar 90 is shifted back and forth between its drive and lockposition by a clutch collar actuating means 9S. In this instance, theactuating means comprises an electrical solenoid 100 mounted on thebreech frame 36 adjacent the clutch collar. Pivotally mountedintermediate its ends on a pin 101 secured to the frame in the regionbetween the clutch collar 98 and the solenoid 101') is a collaractuating lever 102. One end of this lever is shaped to provide a fork104 which straddles the collar within an external groove 106 extendingcircumferentially about the collar. The opposite end of the lever 102.is pivotally attached to the solenoid plunger S. Embodied in thesolenoid 100 are means, such as a spring, for axially urging thesolenoid plunger 108 in a direction to shift the clutch collar 90 to itstransfer wheel locking position when the solenoid is de-energized.Energizing of the solenoid drives the plunger in the opposite directionto shift the clutch collar to its transfer wheel driving position.

It will be recalled that in addition to the ammunition transfer means20, the ammunition feed mechanism 14 includes an ammunition infeed means18 for conveying the ammunition rounds 16 in succession to the infeedtransfer station Si of the transfer means. Referring to FIG. 2, it willbe observed that this infeed station is located generally diametricallyacross the transfer wheel 22 from the outfeed transfer station S0. Theillustrated ammunition infeed means 18 includes an ammunition infeedguide 110 having rigid -walls defining an interior infeed guide passage112 of rectangular cross-section. The infeed guide is rigidly secured tothe breech frame 36 in such a way that the outfeed end of the interiorguide passage opens to the infeed transfer station Si in the directionof rotation of the transfer wheel 22 through this station and in generaltangential relation to the drum. Extending circumferentially about thetransfer wheel drum 54 in radially spaced relation thereto and in thedirection of rotation thereof, from the outfeed end of the infeed guide110 to the breech frame 36 of the gun 34 is a curved ammunitionretaining guide 114. This retaining guide is rigidly joined to theinfeed guide and breech frame and is cylindrically curved about therotation axis of the transfer wheel 22. Along the longitudinal edges ofthe retaining guide 114 are ammunition retaining flanges 116 whichextend inwardly toward the axis in endwise straddling relation to thetransfer wheel drum 54.

The infeed guide 110 is connected, either directly or through anintervening feed chute (not shown), to the ammunition magazine 17 or thelike for containing a supply of the ammunition rounds 16. The interiorpassages within the feed chute and/or infeed guide 110, as the case maybe, are sized to slidably receive the ammunition rounds 16 with the axesof the rounds extending normal to the length of the passages. It will beunderstood, therefore, that these passages are sized to permit lateralmovement of the rounds to the infeed transfer position S1 of thetransfer wheel 22.

As will be described in greater detail presently, the ammunition rounds16 move laterally in succession from the infeed guide 110 to theammunition transfer wheel 22 and are then conveyed or transported bythis wheel from the infeed transfer position Si to the outfeed transferposition So. In this regard, it will be recalled that the transfer wheelis equipped with article receiving means 24 into which the ammunitionrounds enter in succession at the infeed station. These articlereceiving means serve to drive the rounds with the transfer wheel aswell as to accurately space the rounds along and orient the rounds in apredetermined attitude relative to their direction line of movement withthe transfer wheel. In this instance, the article receiving meanscomprise ammunition receiving pockets 118 which are spacedcircumferentially about and open laterally through the circumference o-fthe transfer wheel and are defined by a number of circumferentiallyspaced, ammunition drive pawls 120 carried by the wheel. The severaldrive pawls 120 are arranged in pairs 120H. AS shown best in FIG. 3, thetwo pawls of each pair are aligned lengthwise of and located adjacentopposite ends of the transfer wheel drum 54. The several pawl pairs areuniformly circumferentially spaced about the drum.

The several drive pawls 120 at each end of the transfer wheel drum 54are identical and the two pawls of each pawl pair are mirror images ofone another. Accordingly, the same description will apply, with certainhereinafter noted minor exceptions to all of the pawls With this inmind, each drive pawl will be seen to have a generally L-shape and tocomprise a pair of arms 1200, 120i which are joined end-to-end ingenerally mutually perpendicular' relation. For reasons which willappear as this description proceeds, the two arms 1200, 120i of eachpawl are hereinafter referred to as outer and inner arms, repsectively.Integrally formed on and extending inwardly from the inner edge of theouter arm 120o of each pawl, adjacent the free end of this arm, is anapertured lug 122. This lug has the same thickness as and is disposed inthe common plane of the arms. The free end of each outer pawl arm 1200,beyond its lug 122, is contoured to define a concave ammunition seatingface 124. The inner end of the seating face 124 on each pawl mergestangentally with the adjacent edge of the respective lug 122. The outerend of the seating face on each pawl curves outwardly to provide thepawl with a generally tapered and terminally rounded tip 126. Referringto FIG. 3, it will be observed that the two drive pawls 120 in each pawlpair 120a have confronting surfaces. Secured to the free or inner endsof the inner arms 120, of the pawls in each pair are cam followers 128which project laterally from the confronting surfaces of the pawls. Itwill now be recognized therefore, that the several ammunition drivepawls 120 are identical except for the fact that the cam followers 128on the pawls adjacent the front end of the transfer wheel drum 54project from the rear sides of the pawls, while the cam followers on therear pawls project from the front sides of the latter pawls.

The transfer wheel drum 54 has a number of circumferential slots 130,one for each of the drive pawls 120. Each slot receives the inner arm120i and lug 122 of its respective pawl. The pawls are pivotally mountedin their respective transfer wheel slots by pins 132 which are pressfitted in the transfer wheel drum and extend across the drum slots 130and through the apertured pawl lugs 122. The several drive pawls areoriented in the same general position relative to the transfer wheel. Inthis connection, it will be observed that the lugs 122 and inner arms120o of the pawls are located within the front and rear ends,respectively, of the respective wheel slots 130, relative to thedirection of rotation of the transfer wheel 22. Accordingly, theammunition seating face 124 of each pawl is located at the leading endof the pawl and faces forwardly relative to the direction of transferwheel rotation. It is also significant to observe that the arnmunitionseating face of each pawl projects beyond the outer surface of thetransfer wheel drum 54. The breech cylinder 12, breech frame firingstrap 50, and infeed guide have clearances lots 12a, 50a, and l10n,respectively, through which the projecting leading ends of the pawlspass during rotation of the transfer wheel.

As noted earlier, the transfer wheel drum surrounds a cam assembly 70including an inner xed drum supporting mem-ber 72. In addition to thissupporting member, the cam assembly comprises an annular can 134 whichsurrounds and is keyed to the rear shaft 78 of the supporting member.This lcam is straddled in the endwise direction by the inwardlyprojecting inner arms 120i of the ammunition drive pawls 120. Machinedor otherwise formed in the end faces of the cam 134 are annular camgrooves or tracks 136 which receive the cam followers 128 on the pawls.It is evident from the description thus far, therefore, that when theammunition transfer wheel 22 is driven in rotation by the breechcylinder drive motor 46, the drive pawl cam followers travel along theirrespective receiving cam tracks 136. These cam tracks are shaped topivot or rock the pawls 120 on their respective pivot axes in the mannerto be explained presently.

It will be recalled that the ammunition rounds 16 are adhesively bondedto one side of the conveyor web or ammunition belt 32. This belt istrained through the ammunition feed mechanism 14 in the manner bestillustrated in IFIGS. 2 and 3. In this regard, it will be observed thatthe belt extends through the ammunition infeed guide 110 to the infeedtransfer station Si, around the transfer wheel drum 54 from the infeedstation to the outfeed transfer station S0, and finally emerges througha narrow clearance gap between the drum and the breech frame ring strap50 of the open chamber gun 32. It is significant to recall here that theammunition rounds 16 are somewhat longer than the width of the belt 32and that the ends of the rounds project a distance beyond thelongitudinal edges of the belt. In this regard, it will be observed thatthe width of the belt approximates or is slightly less than the spacingbetween the ammunition drive pawls 120 in each vof the pawl pairs 120aon the ammunition transfer wheel 22. The length of the ammunitionrounds, on the other hand, is somewhat greater than this spacing.According to the present invention, the ammunition belt is trained aboutthe transfer wheel in such a Way that the belt passes between the drivepawls in direct seating contact with the surface of the transfer Wheeldrum 54, and the leading ammunition seating faces 124 of the pawlsengage the extending ends of the ammunition rounds on the belt.Accordingly, when the transfer wheel 22 is driven in rotation by thebreech cylinder drive motor 46, the pawls 120 drive their respectiveengaged ammunition rounds 16 in rotation with the transfer wheel. Thedriving forces thus exerted on ammunition rounds are transmitted to thebelt 32 and serve to pull the latter, and the incoming ammunition roundssecured thereto, from the ammunition magazine 17 through the infeedguide 110, to the transfer wheel. It will be understood, of course, thatthe spacing between the rounds approximates the circumferential spacingbetween the drive pawl ammunition seating faces 124 such that the roundsare properly located on the ammunition belt 32 for driving engagement bythe pawls. At this point, it is evident that the articles or ammunitionrounds 16, transfer wheel 22, and web or belt 32 together constitute anarticle transport mechanism for transporting the articles, i.e.,ammunition rounds, in the endwise direction of the belt. The transferwheel functions as a sprocket-like drive wheel for driving the beltendwise. As noted earlier, and hereinafter explained in greater detail,the ammunition rounds are stripped from the belt at the outfeed transferstation So and simultaneously transferred into the firing chambers 30 ofthe currently rotating breech cylinder 12.

The ammunition feed mechanism 14 is equipped with disposal means 138 forreceiving and disposing of the stripped end of the conveyor web orammunition Fbelt 32 emerging through the narrow gap between the breechframe ring strap 50 and the transfer wheel drum 54 when the open chambergun 34 is fired. Various disposal means may be utilized for thispurpose. In this instance,

the disposal means comprises a disposable takeup reel 140. Referringparticularly to FIGS. 2 and 3, it will be Dbserved that the takeup reelis positioned between a pair of integral laterally projecting lugs 142,144 on the gun frame 36, just below the ejection chute 52. Mounted onthe front lug 142 is a constant torque motor 146 having a shaft 148which extends rotatably through the lug. The rear projecting end of theshaft is squared and fits slidably within a square socket 150 in thefront of the takeup reel 140. Entering the rear end of the reel is asocket 152 which slidably receives the front end of a reel supportingshaft 153. Shaft 153 is supported for rotation and axial movement in therear frame lug 144. Surrounding the shaft adjacent the reel is anenlarged shoulder 154 which slides within a front counterbore in thelug, as shown. A spring 155 acting between the shoulder and the rearwall of the counterbore urges the shaft 153 forwardly to its position ofFIG. 3. In this position, the front end of the shaft lits in the rearreel socket 152 and the shaft shoulder 154 seats against the reel. Thetakeup reel is then supported lby the motor shaft 148 and shaft 153 withits axis parallel to the rotation axes of the breech cylinder 12 and thetransfer wheel 22. The constant torque motor 146, when energized, drivesthe reel in the clockwise direction in FIG. 2. On the rear end of thereel shaft 153 is a knurled grip 156 by which the shaft may be retractedto release the takeup reel 140 for removal. In this regard, it would benoted that the spacing between the frame lugs 142, 144 is sucient topermit removal and reinsertion of the takeup reel. The hub of the takeupreel has a slot 158 to receive the leading end of the belt 32 forsecuring the latter to the reel. Rotatably mounted :between the framelugs, in the region between the transfer wheel 22 and the takeup reel140, is a roller 160 about which the belt passes from the wheel to thereel as shown.

The operation of the gun system 10iy will now be described. The systemis conditioned for firing by initial threading the ammunition belt 32through the infeed guide 112, around the transfer wheel 22, through theclearance gap between the transfer wheel and the breech frame firingstrap 50, and around the roller 160` to the takeup reel 140. The leadingend of the belt is then inserted into the reel slot 158 to secure thebelt to: the takeup reel. In this regard, it will be understood that theammunition belt 32 will be provided with a leader portion which may bethreaded through the system and secured to the takeup reel, in themanner just explained. When thus threading the ammunition belt throughthe system, at least the leading ammunition round 16 on the belt islocated to be engaged by a pair of the drive pawls 120 on the transferwheel 22 when the latter is driven in rotation. At this point, thebreech cylinder drive motor 46 and the takeup reel drive motor 146 areenergized. Motor 46, when energized, drives the breech cylinder 12 inrotation in a counterclockwise direction in FIG. 2. However, assumingthat the transfer wheel clutch actuating solenoid 100 is deenergized,the transfer wheel 22 remains stationary so that no ammunition roundsare fed to the cylinder. Under these conditions, the takeup reel 140remains stationary even though its drive motor 146 is energized. This isdue, of course, to the constant torque characteristics of the motor. Thegun system 10 is now conditioned for 4tiring operation.

Actual ring operation of the gun system 10 is initiated by energizingthe transfer wheel clutch actuating solenoid 100 to effect driving ofthe ammunition transfer wheel 22 in synchronism with the currentlyrotatably breech cylinder 12. This rotation of the transfer wheelresults in driving engagement of the transfer Wheel pawls 120 with oneor more of the leading ammunition rounds 16 on the ammunition belt 32.The ammunition belt and the ammunition rounds attached thereto arethereby driven in the endwise direction of the belt from the ammunitionmagazine 17, through the infeed guide 112, to the infeed l 1 transferstation Si. At this station, the belt and ammunition rounds enter ontothe transfer wheel and travel with the latter from the infeed transferstation to the outfeed transfer station So. As noted earlier andhereinafter explained in detail, the ammunition rounds and ammunitionbelt are directed along divergent paths as they approach and then travelthrough the outfeed station. In this regard, it will become evident fromthe ensuing description that each ammunition round, upon approaching theoutfeed station, enters a breech cylinder firing chamber 30 and thentravels with the chamber, along its circular direction line of movement,from the outfeed station, through firing position opposite the breechframe firing strap 50, to ejection position opposite the ejection chute52. The ammunition belt, .on the other hand, follows an exit path fromthe outfeed transfer station which leads through the narrow exit gapbetween the transfer wheel and firing strap, then around the idlerroller 1601, to the takeup reel 140. This movement of the ammunitionround and ammunition belt along divergent paths results in stripping ofthe rounds from the belt, thus to release the rounds from the belt forfiring in the open chamber gun 34. Endwise movement of the stripped endof the ammunition belt along its exit .path permits rotation of thetakeup reel 140 by its constant torque drive motor 146, whereby the beltis wound on the reel. Thus, during firing operation of the gun system10, the ammunition rounds 16 are dispensed or transferred laterally insuccession from the ammunition belt 32 to the rotating breech cylinderfiring chambers 30, while the ammunition belt is continuously disposedof by winding of the belt on the takeup reel 140. Each ammunition roundis fired as it rotates through ring position, after which the spentcartridge case of the round is rotated to ejection position and thereejected through the ejection chute 52. In this connection, attention isdirected to FIG. 2, in which it will be observed that the gun 34 isequipped with a pair (only one shown) of cartridge case ejection cams162. These cams are secured to the breech frame 36, along the trailingedge of the ejection chute 52 relative to the direction of rotation ofthe breech cylinder 12, and project radially inward into the transferwheel drive pawl clearance grooves 12a. The leading edges of these camsare disposed at an acute angle relative to the circular direction lineof movement of the breech cylinder firing chambers 30. Accordingly, thecams are effective to cam the cartridge cases of the fired ammunitionrounds laterally from their containing firing chambers 30 into theejection chute 52 during rotation of the chambers through ejectionposition.

At this point, attention is directed to the fact that the breechcylinder 12 and transfer wheel 22 are driven at substantially the samerim velocity. In this regard, it will be observed that the transferwheel is smaller in diameter than the cylinder and is thus driven at ahigher angular velocity than the cylinder. To this end, the transferwheel drive gears 86, 88 are selected to have the correct ratio to drivethe wheel at the same rim speed as the cylinder. Moreover, the numbersand spacings of the cylinder firing chambers 30 and transfer wheel drivepawls 120 and the cylinder and transfer wheel diameters are so relatedthat each ammunition round 16 will arrive at the outfeed transferstation So concurrently with a firing chamber and then undergo lateralinfeed movement into the chamber in the manner shown in FIG. 2 as thechamber and round travel in unison through the station.

The above-described firing operation of the gun system continues as longas the transfer wheel clutch actuating solenoid 100 remains energized.De-energizing of this solenoid terminates rotation of the transfer wheel22 and hence feeding of the ammunition rounds 16 to the rotating breechcylinder 12. Under these conditions, firing of the open chamber gun 34ceases. Accordingly, it is evident that the gun 34 may be firedcontinuously or in bursts, as desired, by appropriately controlling thetransfer wheel clutch actuating solenoid. It should be noted here thatthe drive mechanism 86, 88, 90, and 92 for the transfer wheel 22 is soconstructed and arranged, as by selection of the proper number andspacing of the clutch teeth 92, that the rotation of the breech cylinderand transfer wheel will be correctly synchronized in every engagedposition of the clutch teeth for proper entrance of the ammunitionrounds into the firing chambers. After the ammunition magazine 17 hasbeen emptied, the takeup reel 140, which will then contain the entirelength of the spent ammunition belt 32, is removed and replaced by anempty reel to permit reloading of the gun.

Returning now to the transfer wheel 22, it will be recalled that itsdrive pawls have cam followers 148 which travel along the cam grooves136 during rotation of the transfer Wheel. In FIG. 2, it will beobserved that the cam grooves are shaped to rock the pawls back andforth on their pivot aXes in timed relation to rotation of the transferwheel. Thus, as each pawl approaches the outfeed transfer station S10,the pawl is rotated in the counterclockwise direction in FIG. 2 to theposition illustrated at the upper left-hand portion of the transferwheel in the figure. In this position, the front ammunition seating face124 of each pawl is disposed substantially normal to or inclinedrearwardly at a slight angle relative to the circular direction line ofmovement of the pawl With the transfer wheel. Each drive pawl remains inthis position until it emerges from the outfeed transfer station. Thepawl is then rotated in the clockwise direction in FIG. 2 to theposition occupied by each pawl on the lower half of the transfer wheelin the figure. In this latter position, the ammunition seating face ofeach pawl inclines forwardly at a small angle relative to its circulardirection line of movement so as to define, with the cylinder surface ofthe transfer wheel drum `54, a forwardly opening generally V-shapedpocket for receiving the radially inner trailing apex edge of theadjacent ammunition round 16.

The reason for this rocking motion of the transfer wheel ammunitiondrive pawls 120 will now be explained. As noted earlier, the ammunitionbelt 32 travels around the transfer wheel 22 in seating contact with thetransfer wheel drum 54 in the region between the pawls. Accordingly,each ammunition round 16 on the transfer Wheel is disposed with onecurved face of the round adjacent and facing the drum and with theopposing apex edge of the round located radially outward of the drumsurface. Referring to FIG. 2, it will be seen that as each ammunitionround approaches the outfeed transfer station So, the round undergoeslateral infeed movement into a breech cylinder firing chamber 30,through the open side of the chamber, in such a way that the trailingwall of the chamber initially contacts the outer apex of the round.During continued rotation of the round and firing chamber through theoutfeed transfer station, the trailing chamber wall exerts a clockwisemoment, as viewed `in FIG. 2, on the round which rotates or pivots theround forwardly in the direction of its rotation, about the innerleading apex edge of the round as a fulcrum, to a position wherein theround is disposed for full seating engagement within the chamber. Thisforward rotation of each round swings the inner trailing apex edge ofthe round radially outward away from the transfer wheel. The ammunitionseating faces 124 of the transfer wheel ammunition drive pawls 120 arerotated rearwardly, in the manner just explained, as they approach theoutfeed transfer station in order to accommodate this forward pivotingof their engaged ammunition rounds 16 without jamming of the ammunitionrounds against the pawls. The drive pawl ammunition seating faces arethen rotated forwardly as they emerge from the outfeed transfer stationto provide the aforementioned forwardly open, generally V-shaped pocketsfor receiving the inner trailing apex edges of the following incomingammunition rounds. Referring to the lower half of the transfer wheel inFIG.

2, it will be seen that these pockets are shaped to generally complementthe apex edges of the ammunition rounds, thus to effect secure drivingengagement of the drive pawls with the ammunition rounds.

As noted earlier, the ammunition rounds 16 and ammunition belt 32 aredirected along divergent paths as they approach and travel through theoutfeed transfer station 22 in such a way that the rounds are strippedfrom the ammunition belt, or the belt is stripped from the rounds, tofree the rounds from the belt for rotation of the rounds with theircontaining tiring chambers through ring position to ejection position inthe manner explained earlier. The transfer guide 26 aids or effects thisstripping action. In this instance, the transfer guide comprises arelatively sharp tapered leading edge of the bree-ch frame tiring strap50. Referring to FIG. 2, it will be seen that the tapered transferIguide or edge 26 functions, effectively, as a wedge which entersbetween the ammunition belt 32 and each ammunition round 16, as thelatter travels through the outfeed transfer station. This wedge directseach round laterally upwardly in FIG. 2 into and then along the curvedpath of motion of its containing tiring chamber 30l and the beltdownwardly along its curved exit path. Each round is thereby separatedfrom the belt by a stripping action. In this regard, it is significantto recall that the ammunition rounds 16 are secured to the ammunitionbelt 32 by adhesive having a relatively high shear strength and arelatively low peel strength, such that the driving forces exerted onthe rounds by the transfer wheel drive pawls 120 are effectivelytransmitted to the ammunition belt, for driving the latter and theincoming ammunition rounds attached thereto, while permitting strippingof the rounds from the belt at the outfeed transfer station.

What is claimed is:

1. An open chamber gun system comprising:

:an open chamber gun including a breech frame, a rotary ammunitioncylinder inV said frame having circumferentially spaced ring chambersextending longitudinally of and opening laterally through thecircumference of said cylinder and rotatable in succession through anammunition infeed station and a following firing station, and means fordriving said cylinder in rotation; and

an ammunition feed mechanism including an ammunition belt, open chamberammunition rounds extending laterally of said belt in generallyuniformly spaced relation along said belt, said ring chambers andammunition rounds having complementary generally triangular round shapesin transverse crosssection and said rounds having curved sidesreleasively adhesively bonded to one surface of said belt, means forfeeding said belt and ammunition rounds in one endwise direction of saidbelt along a prescribed path of motion merging generally tangentiallywith said cylinder at said infeed station with said one surface of saidbelt facing said cylinder at said infeed station in such a way that saidammunition rounds and firing chambers undergo unified lateral movementin the same direction through said infeed station and each ammunitionround enters the corresponding firing chamber laterally apex rst at saidinfeed station, and a wed-ge shaped formation on said breech frame forstripping each ammunition round from said belt at said infeed station,directing each stripped round laterally into its respective firingchamber for movement with the chamber along its circular path of motionto said ring station, and directing said belt :along an exit pathdivergin-g from said circular path.

2. An open chamber gun system comprising:

an open chamber gun including a breech frame having a firing strap, acylinder rotatable in said frame and containing axially extendingcircumferentially spaced firing chambers opening laterally through thecircumference of said cylinder, and means for driving said cylinder inrotation whereby said firing chambers undergo rotation in successionthrough an arnmunition infeed position wherein the open side of eachring chamber registers with an ammunition infeed opening in said frame,a firing position wherein the open side of the respective chamber isclosed by the breech frame firing strap, and an ejection positionwherein the open side of each chamber registers with an ejection openingin said breech frame; and

an ammunition feed mechanism including a rotary transfer wheel disposedin generally tangential relation to said cylinder through said infeedopening with the axis of said wheel parallel to the axis of saidcylinder, an ammunition belt trained about said transfer wheel with onesurface of said belt disposed in seating engagement with said wheel,open chamber ammunition rounds extending laterally of and adhesivelybonded to the other surface of said belt in generally uniformly spacedrelation along said belt, the ends of said rounds projecting beyond thelongitudinal edges of said belt, radially projecting `drive pawlscircumferentially spaced about said transfer wheel at opposite sides ofsaid belt and disposed in driving engagement with the extending ends ofthe ammunition rounds on said wheel, whereby during rotation of saidtransfer wheel said pawls exert on said rounds driving forces which aretransmitted to said belt for transporting said belt and its attachedammunition rounds in the endwise direction of said belt, means fordriving said transfer wheel in rotation in unison with and in a`direction opposite the direction of rotation of said cylinder, wherebysaid ring chambers and ammunition rounds undergo unied rotation in thesame direction through said infeed position, and transfer means at saidinfeed position for stripping each round arriving at said latterposition from said belt and laterally transferring the stripped roundfrom said transfer wheel into the corresponding firing chamber of saidcylinder.

3. A gun system according to claim 2, wherein:

said firing chambers and ammunition rounds have complementary generallytriangular round shapes in transverse cross-section;

said ammunition rounds have curved sides thereof adhesively bonded tosaid web, whereby each ammunition enters its respective firing chamberapex first in such a way that the trailing wall of each ring chamberexerts a moment on its respective entering round for rotating the roundforwardy in the direction of its rotation with said transfer wheel to aposition wherein the respective round is disposed for proper entranceinto the tiring chamber;

said pawls have forward ammunition seating faces disposed for seatingengagement with said ammunition rounds, and said pawls are rotatablerelative to said transfer wheel on pivot axes parallel to the axis ofsaid transfer wheel between extended positions wherein said seatingfaces incline forwardly relative to the direction of rotation of saidtransfer wheel to define generally V-shaped pockets for receiving thetrailing apex edges of said ammunition rounds and retracted positionswherein said seating faces extend generally radially of said transferwheel, means pivotly supporting said pawls on said transfer wheel forrocking between said positions, and a cam means for rocking said pawlsbetween said positions in timed relation to rotation of said transferwheel in such a way that said pawls are rocked to their retractedpositions as they approach an outfeed transfer station wherein saidammunition rounds undergo transfer movement from said transfer wheel tosaid cylinder and to their extended positions as said pawls approach andinfeed transfer station wherein said belt enters onto said transferwheel.

4. A gun system according to claim 3, wherein:

said transfer means comprises a relatively sharp wedgelike edge on saidbreech frame firing strap which enters between said belt and eachammunition round arriving at said outfeed transfer station; and

an infeed guide opening tangentially to said transfer wheel at saidinfeed transfer station for guiding said ammunition belt and ammunitionrounds along a prescribed path of motion merging tangentially with saidtransfer wheel at said infeed transfer station.

5. An open chamber gun system comprising:

an open chamber gun including a breech frame, a rotary ammunitioncylinder in said frame having circumferentially spaced firing chambersextending longitudinally of and opening laterally through thecircumference of said cylinder and rotatable in succession through anammunition infeed station and a following firing station, and means fordriving said cylinder in rotation; and

an ammunition feed mechanism including an ammunition belt, open chamberammunition rounds extending laterally of said belt in generallyuniformly spaced relation along said belt, said firing chambers andammunition rounds having complementary generally triangular round shapesin transverse crosssection and said rounds having curved sidesreleasively adhesively bonded to one surface of said belt, means forfeeding said belt and ammunition rounds in one endwise direction of saidbelt along a prescribed path of motion merging generally tangentiallywith said cylinder at said infeed station with said one surface of saidbelt facing said cylinder at said infeed station in such a way that saidammunition rounds and tiring chambers undergo unitied lateral movementin the same direction through said infeed station and each ammunitionround enters the corresponding firing chamber laterally apex first atsaid infeed station, and means at said infeed station for stripping eachammunition round from said belt, directing each stripped round laterallyinto its respective firing chamber for movement with the chamber alongits circular path of motion to said tiring station, and directing saidbelt along an exit path diverging from said circular path.

6. An open chamber gun system according to claim 5,

wherein:

said belt feeding means is intermittently operable to effect selectiveintermittent feeding of said ammunition rounds to said gun.

7. An open chamber gun system according to claim 5,

including:

a take-up reel rotatably supported on said breech frame and secured tothe stripped end of said belt, and means for driving said take-up reelto Iwind said belt on said reel.

8. An open chamber gun system according to claim 7,

including:

a releasable driving connection between said take-up reel and reeldriving means, whereby said take-up reel may be removed from said gunwhen said belt is fully wound on said reel.

9. An open chamber gun system comprising:

an open chamber gun including a breech frame having a tiring strap, acylinder rotatable in said frame and containing axially extendingcircumferentially spaced ring chambers opening laterally through thecircumference of said cylinder, and means for driving said cylinder inone direction of rotation;

an ammunition transfer wheel rotatably supported on said frame with theaxis of said wheel parallel to the axis of said cylinder and protrudingthrough an ammunition infeed opening in said frame into generallytangential relation with said cylinder within a first transfer station,said transfer wheel including means defining a number of ammunitionreceiving pockets spaced circumferentially about and opening laterallythrough the circumference of said wheel, whereby a firing chamber and anammunition pocket situated at said station open laterally toward oneanother;

said cylinder being rotatable in said one direction to rotate saidtiring chambers in succession through said transfer station and afollowing firing station, wherein the open side of each firing chamberis closed by said breech frame firing strap, and said transfer wheelbeing rotatable in the opposite direction to rotate said ammunitionpockets in succession through said transfer station and a secondtransfer station wherein each pocket is disposed to receive anammunition round;

means for driving said cylinder and transfer wheel in unison to causeunified lateral movement of said firing chambers and ammunition pocketsin the same direction through said rst transfer station in a manner suchthat each firing chamber and an ammunition pocket undergo lateralmovement through said first transfer station in unison with therespective chamber and pocket opening laterally toward one another; asupply of open chamber ammunition rounds, said rounds and tiringchambers having complementary generally triangular round shapes intransverse crosssection;

infeed means for feeding said ammunition rounds laterally in successionto said transfer wheel at said second transfer station in such a waythat each ammunition round enters a transfer pocket at said secondtransfer station and thereafter rotates with its containing pocket tosaid first transfer station;

said transfer wheel pockets being generally tapered in transversecross-section to orient their contained ammunition rounds with apiciesof the respective rounds disposed radially outward relative to saidtransfer wheel in such a way that each ammunition round on said transferwheel approaches said rst transfer station concurrently with a cylinderfiring chamber and enters the respective tiring chamber laterally apexfirst as the respective -chamber and round travel through said firsttransfer station;

means at said first transfer station for effecting lateral movement ofeach ammunition round arriving at said first transfer station from saidtransfer wheel into its receiving cylinder firing chamber for subsequentrotation of the respective round with its receiving chamber to firingposition; and

said gun including means for tiring each ammunition round in said firingposition.

10. An open chamber gun system according to claim 9, wherein:

said driving means comprises means for selectively intermittentlydriving said transfer wheel in unison with said cylinder to effectselective intermittent feeding of said ammunition rounds to said gun.

11. The method of feeding open chamber ammunition rounds of generallytriangular round shape in transverse cross-section to an open chambergun, said rounds having one curved side adhesively bonded to one surfaceof an ammunition belt with the rounds extending transversely of saidbelt in generally uniformly spaced relation along the belt, and said gunincluding a rotary cylinder having firing chambers of said triangularround shape in transverse cross-section spaced circumferentially aboutand opening laterally through the circumference of said cylinder, saidmethod comprising the steps of:

driving said cylinder in one direction of rotation to cause lateralmovement of said firing chambers in succession through an ammunitioninfeed station and a following tiring station; and

feeding said belt endwise through said infeed station along an arcuatepath of motion which merges tangentially with the circumference of said|cylinder at said station With said one surface of said belt facing saidcylinder with apices of the rounds presented toward and in apredetermined attitude relative to said 'circular path in such a Waythat each ammunition round approaches said station concurrently with aring chamber and enters the tiring chamber laterally, apex rst, throughthe open side of the respective ring chamber during7 lateral movement ofthe firing chamber and ammunition round through said station, each roundis then stripped from said belt at said station and transported by itscontaining firing chamber from said infeed station to said firingstation, and said belt emerges from said station along an exit pathwhich diverges from said cylinder.

References Cited UNITED STATES PATENTS 8/1885 Allender 89-12 3/1891Skoda 89-3'3 X 8/1892 Garland 89`35 4/ 1958 Dardick 89-33 X 9/1958 Otto89-12 11/1960 OBrien 89-33 X .8/ 1961 Kunz.

7/1964 Double 221-73 7/1967 Kraus 89-33 7/1962 Dardick 89-160 X FOREIGNPATENTS Y 1888 Great Britain. 8/1938 Great Britain.

SAMUEL FEINBERG, Primary Examiner S. C. BENTLEY, Assistant Examiner

